Carbonic anhydrase II expression in fibrous astrocytes of the sheep

Immunohistochemical expression of carbonic anhydrase isoenzyme II (CAII) was demonstrated in a population of fibrous astrocytes in a young lamb and an adult sheep. Such cells were identified by co-expression of CAII and glial fibrillary acidic protein, nuclear morphology and their contribution of glial fibrillary acidic protein reactive processes to the glial limitans. Similar cells were not identified in neonatal lambs. As in man and mouse, CAII was also expressed in choroid plexus epithelium occurring in neonate, young and adult sheep brain. In contrast, however, to man and mouse, CAII was not expressed in sheep oligodendrocytes.     

The B- to Z-DNA equilibrium in vivo is perturbed by biological processes.

Right-handed B and left-handed Z conformations coexist in equilibrium in portions of plasmids in Escherichia coli. The equilibria are influenced by the length of the sequences that undergo the structural transitions and are perturbed by biological processes. The composite results of three types of determinations indicate a supercoil density of -0.025 in vivo. The coexistence of alternative DNA conformations in living cells implies the potential of these structures or their transitions for important functions in genetic regulatory processes.     

Ankylosing spondylitis antirheumatic drug trials. III. Setting the delta for clinical trials of antirheumatic drugs--results of a consensus development (Delphi) exercise.

Defining the minimum clinically important difference or delta to be detected in a clinical trial depends on a number of factors including the research hypothesis, patient characteristics, the nature of the intervention and the trial design. In 2 previous studies, we have developed standardized procedures for conducting outcome measurement based on current Food and Drug Administration and European League Against Rheumatism guidelines for clinical trials in ankylosing spondylitis, and thereafter, determined the standard deviation for these outcome measures. In the final component of this series of studies, we have employed a Delphi technique to establish estimates for delta, and calculated the sample size requirements under 2 different conditions of Type I and Type II error probabilities.     

The value of myocardial perfusion single-photon emission computed tomography in screening asymptomatic patients with atrial fibrillation for coronary artery disease.

OBJECTIVES: We sought to determine if screening for coronary artery disease (CAD) with stress single-photon emission computed tomography (SPECT) is of value in patients with atrial fibrillation (AF) who do not have symptoms of chest pain or dyspnea. BACKGROUND: Although noninvasive stress testing is often done to screen for CAD in asymptomatic patients with AF and is considered to be appropriate in selected patients, its potential utility has not been demonstrated. METHODS: A retrospective study was conducted of 374 asymptomatic patients with AF referred for the detection of CAD. Mean follow-up was 5.7 +/- 3.8 years. The study group was compared with a control group of 374 asymptomatic age and gender-matched patients without AF. RESULTS: The mean summed stress score (SSS) was not significantly different between AF patients and control subjects (3.6 +/- 5.3 vs. 3.5 +/- 5.9; p = 0.35). Compared with controls, asymptomatic AF patients had similar rates of abnormal SPECT studies (51.6% vs. 48.4%; p = 0.38) and high-risk studies (14.4% vs. 14.4%; p = 1.0). The SSS was a significant predictor of outcome in both AF patients and control subjects. However, total mortality was significantly greater in AF patients (5-year overall mortality 27% vs. 18%, 10-year overall mortality 47% vs. 40%; p < 0.001), and this difference persisted (p = 0.01) after adjusting for multiple clinical variables and the SSS. CONCLUSIONS: Screening for CAD using stress SPECT in asymptomatic AF patients has a yield similar to age- and gender-matched control patients without AF. Although SSS predicts mortality in patients with and without AF, patients with AF have increased total mortality independent of the findings on stress SPECT. These results suggest that factors other than obstructive CAD are responsible for the increased mortality in AF.     

Chrysomya megacephala (Diptera: Calliphoridae) has reached the continental United States: review of its biology, pest status, and spread around the world

Chrysomya megacephala (F.), an Old World calliphorid of considerable public health importance, was first discovered in Brazil in 1977 and is now widely distributed in Latin America. Reports that this species has become established in southern California, and the collection of a specimen in Texas, suggest that C. megacephala may be expanding its range rapidly in North America. The biology and worldwide spread of this pest are reviewed to alert entomologists and public health workers to this growing threat.     

Radiation-induced carcinoma of the penis

Two patients with carcinoma of the penis were treated with interstitial radiation. They were cured of their disease for 17 and 21 years respectively and then developed radiation-induced tumours.     

Familial malignant retroperitoneal paraganglioma

Paragangliomas are neuroendocrine tumours and those occurring in the head and neck have well recognized familial association. Retroperitoneal paragangliomas are uncommon and we present two cases of familial malignant retroperitoneal paraganglioma. Review of the literature revealed marked differences in the incidence and malignant potential of familial and non-familial paraganglioma. In contrast to the cases reported here, familial tumours are generally benign, though they may occur at multiple sites. Familial and non-familial paragangliomas may indeed be different disease entities.